1. Field of the Invention
The present invention relates to a fuel hose for use as a fuel transportation pipe for transporting an automotive fuel such as a gasoline, an alcohol-containing gasoline (gasohol), an alcohol, hydrogen, light oil, dimethyl ether, liquified petroleum gas (LPG) or compressed natural gas (CNG).
2. Description of the Art
As a fuel hose such as a gasoline transportation hose, a hose formed by a polyamide resin has conventionally been used because it is a low-cost material. Examples of such a hose include a multilayered hose formed by laminating a resin layer other than polyamide resin on a polyamide resin layer as well as a single-layer hose formed only by a polyamide resin. However, even in such a multilayered hose, a polyamide resin is generally used as an innermost layer because it is excellent in fuel resistance and low-temperature impact resistance.
If static electricity is generated by abrasion between an inner surface of the above-mentioned fuel hose and the fuel such as gasoline which flows in the hose, accidents such as ignition of a fuel (gasoline) may occur. To help prevent accidents, it is very important that electrical conductivity (antistatic property) is imparted to the hose so as to allow static electricity to escape out of the hose. The electrical conductivity is generally imparted, for example, by involving carbon black in the innermost layer (polyamide resin layer) (for example, see Unexamined patent Publication No. 8-86387).
However, the polyamide resin has a limitation in sour gasoline resistance (resistance to a sour gasoline generated through oxidation of a gasoline) which is an important property required for the fuel transportation hose. In addition, when the polyamide resin includes carbon black, it is thought that the carbon black may activate peroxides in the fuel, which may further aggravate the sour gasoline resistance. If electrical conductivity (antistatic property) is ensured by increasing the amount of the carbon black, substantial amount thereof is required until the desired electrical conductivity is ensured, which may lead to deteriorated sealing property and deteriorated flexibility of the hose.
In view of the foregoing, it is an object of the present invention to provide a fuel hose which is excellent in antistatic property, sour gasoline resistance, a sealing property and the like.